Battery architecture including common components, subassemblies, and method of assembly thereof

Abstract

The system and method for the battery may include cells connected in parallel to form a group and a group of cells connected in series to form a first and second subassembly having components suitable for a plurality of battery configurations. The first subassembly includes a lower cell carrier and an upper cell carrier between which the first group of cells is disposed. The second subassembly includes a lower cell carrier and an upper cell carrier between which the second group of cells is disposed. The flexible current collector includes two or more conductive areas. The first and second subassemblies are connected in parallel or in series to build a desired voltage or capacity of the battery. The flexible current collector is folded around the first and second subassemblies and disposed within a casing to provide environmental protection for the battery, and positive and negative terminals connected to the first and second conductive areas, respectively, form the positive and negative terminals of the battery.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Patent Application No. 17 / 319,170, filed May 13, 2021, which is incorporated herein in its entirety.

[0002] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure generally relate to improved battery architectures that include modular components and subassemblies, and methods of manufacturing the same. [Background technology]

[0003] Original equipment manufacturers' ("OEM") use of lithium-ion batteries for industrial applications is on the rise. Traditionally, lead-acid batteries have dominated commercial applications for batteries. Industrial applications and uses of OEM batteries include powering material handling equipment such as forklifts, scissor lifts, and robots, powering transportation vehicles (i.e., light electric vehicles such as golf carts, and heavy vehicles including automobiles), and diesel generator sets for stationary power applications. Conventional batteries for use in industrial applications contemplate several different form factors and chemistries, including, but not limited to, lead acid, nickel metal hydride ("NiMH"), and lithium ion (LFP, NMC, etc.). With the variety of form factors in commercial use today, replacement of current uses is difficult.

[0004] This wide array of architectures and chemistries results in a wide range of battery sizes and shapes, with multiple batteries connected in series to achieve higher effective voltages. This involves multiple battery assemblies, connectors, and connections, increasing the bill of materials. Traditional approaches have modularized batteries in small units, requiring multiple external connectors and connections, which increases the space occupied by the battery and reduces durability. This has created applications where multiple components are connected by external connections, increasing the size, volume, and weight of the battery assembly, and requiring regular maintenance. Additionally, many parts and connections may be subject to environmental damage and degradation, significantly limiting marine use and reducing the life cycle of the connections and batteries. Traditional batteries are typically configured for voltage classes of 12V, 24V, 36V, 48V, 72V, or other voltage specifications. This range of battery configurations requires a variety of batteries with different energies that are not met by common traditional designs.

[0005] The GC2 form factor is a common battery form factor. There are many different battery voltages in the GC2 form factor, typically 6V, 8V, and 12V, which are connected in series to build both system voltages (typically 12V, 24V, 36V, 48V, 72V, or higher) and increase system stored energy. Lithium-ion technology is a relatively new battery technology and has many advantages over lead-acid, including increased energy density, faster charging, and reduced degradation during long-term storage.

[0006] It would be advantageous to make a lithium-ion "drop-in replacement" for lead-acid batteries to take advantage of the benefits of the new technology without having to reconfigure the space, wiring, battery footprint, and other features of existing applications already developed around the GC2 form factor. However, building voltages using multiple lithium-ion cells (as is done with lead-acid) is expensive due to the additional series connection of multiple cells. Such series connection is unnecessary due to the relatively high energy density of lithium-ion batteries and the increased complexity of connecting lithium-ion cells in series.

[0007] There is a need for improved batteries that are robust, have high energy density and high capacity utilization, provide a lower total cost of ownership, reduce the overall bill of materials, and are fully integrated into a single module. Having a higher energy density while providing a battery that fits into a commercially acceptable form factor increases the energy available to the load and maintains the ability to easily replace conventional batteries in applications with one or multiple form factors. Fully integrated batteries are also more robust, provide longer cycle life, require little or no maintenance due to failure of the interconnects between modules, and have fewer components, all of which translates into a lower total cost of ownership. Additionally, there is a need for improved batteries that can be adapted to various capacity requirements while balancing the remaining bill of materials when configured appropriately by changing only a limited number of parts.

[0008] An improvement over current lithium-ion batteries is also needed by integrating monitoring, measurement, and control functions onto a single circuit board, without the need for a separate housing that is separately wired into the current collectors. Additionally, as energy density increases, so do the safety requirements for the system, so there is a need for a battery system that provides high energy density with improved resistance to abuse.

[0009] There is also a need for improvements to conventional battery assembly methods to produce batteries with increased energy density in commercially acceptable form factors, simpler designs, integrated construction, reduced bills of materials, improved structural integrity, improved durability to the elements (resilience to water ingress, spray, dust, etc.), improved reliability, and increased flexibility in manufacture and use.

[0010] Known methods of assembling batteries typically have a significant bill of materials and multiple assembly and installation steps. The use of multiple fasteners, connectors, fillers and structural components results in multiple parts that are susceptible to fatigue, loosening, damage or failure even from vibrations from normal use. The improved method of assembling batteries eliminates the need and use of multiple fasteners within a module.

[0011] The improved assembly methods disclosed herein also provide for the use of an integrated battery management system ("BMS"). The BMS may be mounted within the battery module case, further reducing the number of components and attachments and minimizing the form factor compared to conventional methods. Some known methods generally use a separate BMS enclosure that requires attachment to the battery or application housing, as well as separate electrical and communication wiring between the battery and the BMS. These improvements help to increase the battery's resistance to water or dust ingress. See, for example, ISO standards IP65 and / or IP67. The improved methods also provide flexibility to adapt to voltage or power requirements while utilizing the same components within the same form factor.

[0012] The disclosed embodiments may include non-conventional battery subassemblies, improved components, and battery assembly methods. Compared to conventional known solutions, the disclosed embodiments may provide improved batteries that fit into commercially acceptable form factors and have certain advantages including one or more of higher energy density, improved resistance to abuse, robustness to environmental shock and intrusion, reduced cost of ownership, and full integration in a single assembly. Other embodiments may include methods of assembling batteries that produce one or more of adaptable form factors, simpler designs, better integrated structures, reduced bill of materials, integrated battery management systems, products that comply with ISO standards IP65 and / or IP67, improved reliability, and improved flexibility of manufacture and use. Summary of the Invention

[0013] The embodiments of the present invention include improved energy density and flexibility. This flexibility can be provided in two ways. First, multiple batteries can be stacked (electrically connected in parallel) to build a capacity that meets the energy requirements of the application. Second, the embodiments of the present disclosure provide a high degree of commonality of components, i.e., by using some or all of the same components in the same form factor (e.g., GC2), a variety of batteries with different voltages and / or capacities can be made. The embodiments of the present invention can achieve this degree of flexibility by changing only a few or preferably one component. Furthermore, this flexibility can be achieved by increasing or decreasing the number of cells included in the battery, thereby changing the energy of the battery without changing any component. This architecture provides great flexibility to the manufacturer or user.

[0014] In embodiments of the present disclosure, cells can be connected into subassemblies and the subassemblies can be electrically connected in a desired configuration to meet desired capacity and / or voltage requirements. In embodiments of the present disclosure, flexibility can mean having a common bill of materials with changes in the number of cells, current collector design, and / or BMS.

[0015] The present disclosure enables cost-effective manufacturing of lithium-ion batteries with any desired form factor at a variety of system-level voltages and capacities. This is accomplished by sharing most internal components between different battery voltages, folding / wrapping current collectors to reduce fasteners and manufacturing costs, allowing cells to be packed more closely together without fasteners and / or other additional structural components, and adding foam to aid in mechanical fixation of the cells.

[0016] In the present disclosure, cells can be connected in parallel to build capacity at the voltage of an individual cell, or in series to build voltage at the capacity of an individual cell. Cells can be electrically connected in series to form a group, and groups of cells can be electrically connected in parallel to form a subassembly. Alternatively, in a preferred embodiment, cells are electrically connected in parallel to form a group, and groups of cells are electrically connected in series to form a subassembly. In a preferred embodiment, a configurable flexible current collector is used to electrically connect two subassemblies to accommodate a preferred form factor of the system. The first subassembly includes a lower cell carrier and an upper cell carrier, between which a first group of cells are disposed. The second subassembly includes a lower cell carrier and an upper cell carrier, between which a second group of cells are disposed. The flexible current collector includes two or more conductive areas. The first and second subassemblies are connected in parallel or in series to build a desired voltage or capacity of the battery. The flexible current collector can be folded and the assembly can be placed in a casing to provide environmental protection for the battery. The positive and negative terminals can be connected to the first and second conductive regions, respectively, to form the positive and negative terminals of the battery.

[0017] The present disclosure achieves higher energy density through one or more of several features. The lower and upper cell carriers are configured to secure the cells in place and resist displacement, positioning the cells in close proximity to one another. The placement of foam in the gaps between the cells enhances safety and robustness against vibration, shock, mechanical displacement, and environmental hazards. This combination of features allows embodiments of the present disclosure to achieve higher energy density. Additionally, the integration of the positive and negative terminals into the BMS and flexible current collectors, as well as the press fit of the components, reduces the number of electrical connections required, thereby facilitating efficient manufacturing and effective electrical connections.

[0018] Batteries including cells can be electrically connected to form groups, and groups of cells can be electrically connected to form first and second subassemblies. The first subassembly can include a lower tray and an upper tray between which the first group of cells is disposed, and the first subassembly can have a first and second side. The second subassembly can include a lower tray and an upper tray between which the second group of cells is disposed, and the second subassembly can have a first and second side. The flexible current collector can include two or more conductive regions; the first and second subassemblies can be electrically connected to build a voltage or capacity of the battery; the flexible current collector can electrically connect the first and second subassemblies and be disposed within the casing to provide environmental protection to the battery; positive and negative terminals can be electrically connected to the first and second conductive regions to form positive and negative terminals of the battery, respectively; and a battery management system can be electrically connected to the flexible current collector and the positive and negative terminals adapted to control the flow of energy through the battery.

[0019] A method of assembling a battery may include inserting cells into inner and outer trays of first and second carriers to form two subassemblies, positioning current collectors, electrically connecting the cells to the current collectors, and folding the current collectors and subassembly.

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments and, together with the description, explain the disclosed embodiments. [Brief description of the drawings]

[0021] [Figure 1] 1 is an exploded schematic view of a battery according to an embodiment of the present disclosure. [Diagram 2] 1A-C are schematic diagrams of a lid according to an embodiment of the present disclosure. [Diagram 3]1A-C are schematic diagrams of two partially assembled subassemblies according to an embodiment of the present disclosure. [Figure 4] FIG. 1 is a schematic diagram of two partially assembled subassemblies with cells positioned within the openings, according to an embodiment of the present disclosure. [Figure 5A] FIG. 2 is a schematic diagram of two subassemblies according to an embodiment of the present disclosure. [Figure 5B] FIG. 2 is a schematic diagram of two subassemblies according to an embodiment of the present disclosure. [Figure 6] FIG. 2 is a schematic diagram of a partially assembled assembly with a flexible current collector attached, according to an embodiment of the present disclosure. [Figure 7] FIG. 2 is a schematic diagram of a partially assembled assembly according to an embodiment of the present disclosure. [Figure 8] 1A and 1B are schematic cross-sectional views of a current collector according to an alternative embodiment of the present disclosure. [Figure 9] 1A and 1B are schematic diagrams of an assembly according to an embodiment of the present disclosure. [Figure 10A] FIG. 2 is a cross-sectional view of an assembly according to an embodiment of the present disclosure. [Figure 10B] FIG. 2 is a schematic diagram of an assembly according to an embodiment of the present disclosure. [Figure 11] 5A-5E are assembly diagrams of a battery according to an embodiment of the present disclosure. [Figure 12] 1 is a flow chart of a method for assembling a battery according to an embodiment of the present disclosure. [Figure 13] 1 shows a current collector for a 24V battery according to an embodiment of the present disclosure. [Figure 14] 1 shows an example of a current collector for a 48V battery, according to an embodiment of the present disclosure. [Figure 15] FIG. 2 illustrates an exploded view of two subassemblies, a flexible current collector, and a heat sink according to an embodiment of the present disclosure. [Figure 16A] 1 shows a 48V battery using a cell carrier according to a preferred embodiment of the present disclosure. [Figure 16B]An alternative 48V battery using the cell carrier of FIG. 16A according to an embodiment of the present disclosure, where some of the cell positions within the carrier are empty, provides lower energy than the embodiment shown in FIG. 16A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Embodiments consistent with the present disclosure may include batteries, components thereof, and improved assembly methods. Cells are preferably connected in parallel to form a group of cells. Groups of cells are preferably connected in series to form a subassembly. A subassembly may include half a cell of a battery. In embodiments of the present disclosure, two or more subassemblies may be connected by flexible current collectors to form a battery. A battery may include a plurality of cells assembled in a housing to protect the cells from external shock, vibration, and environment. Battery cells may be cylindrical or prismatic. The battery may provide nominal voltages of 12V, 24V, 36V, 48V, 72V, or any other suitable voltage depending on device or product specifications. Additionally or alternatively, the battery may be configured to provide non-standard nominal voltages according to specific device or product specifications. Preferred embodiments are configured in 24V, 36V, and 48V classes.

[0023] The embodiments of the present invention provide improved energy density and greater manufacturing flexibility over previously known batteries. The embodiments of the present disclosure feature a high degree of commonality of components, i.e., some or all of the same components can be used in the same form factor to create a variety of batteries with different voltages and / or capacities by changing only a few components, or preferably no components, e.g., by increasing or decreasing the number of cells included in the battery. This improved architecture provides greater flexibility to the manufacturer or user.

[0024] FIG. 1 shows a battery 100 that may include a case 110, a lid 120, an assembly 200 including a first subassembly 201A, a second subassembly 201B, and a current collector 230, and a battery management system (BMS) 300.

[0025] In an example, the case 110 can be sized to receive the assembly 200 and / or to a standard or predetermined dimension. The case 110 can include one or more of an electrically insulating material, a thermal insulator, or a flame retardant material. In another example, the case 110 can be patterned, textured, coated, or ribbed. The case 110 can receive the lid 120, thereby forming a seal between the lid 120 and the case 110.

[0026] 2A-2C are schematic diagrams of a lid 120 that can be sized to receive the assembly 200. The lid 120 can include one or more of an electrically insulating material, a thermal insulating material, or a flame retardant material. In another example, the lid 120 can be patterned, textured, coated, or ribbed. The lid 120 can include a vent 122 (as previously shown in FIG. 1) configured to vent excess gas. The lid 120 can include a lip 121, a vent 122, and / or a vent opening 124. Additionally, the lid 120 can include a first terminal opening 126, a second terminal opening 128, an indicator 130A, an indicator wire harness 130B, an electrical interface 132A, and / or an electrical interface wire harness 132B.

[0027] The indicator 130A may include a display, LED light, color changing strip, or speaker to communicate battery status to a user when the CAN bus of the battery 100 is not utilized. For example, the BMS 300 may change the color or brightness of the indicator to indicate the battery condition. In an example, when the battery charge is low, the BMS 300 may change the color of the indicator from green to red. In another example, when the battery is charging, the BMS 300 may change the brightness of the indicator to produce a visible "blink" or "pulse". In additional alternative embodiments, an audio signal may be provided in addition to or instead of a visual signal.

[0028] Additionally or alternatively, if a CAN bus interface of the BMS 300 is utilized, the BMS can transmit and / or receive data using one or more processors to communicate with one or more batteries connected to the CAN bus interface. The data can include self-identification information (e.g., model, serial number, error codes), information indicative of battery status, and / or information indicative of battery configuration (e.g., series and / or parallel configuration).

[0029] The indicator wire harness 130B may be in electrical communication with the BMS 300 and the indicator 130A and may be configured to transmit data and / or electrical signals to each other.

[0030] The electrical interface 132A may be a receptacle that facilitates data communication between the BMS 300 and an external computing device, such as a computer, a mobile device, or a battery charger, a battery charging station, various vehicle on-board computers or other battery management systems. The electrical interface wire harness 132B may be in electrical communication with the BMS 300 and the electrical interface 132A and may be configured to transmit data and / or electrical signals to each other.

[0031] 3A-3C are schematic diagrams of two partially assembled subassemblies. FIG. 3A shows that the first inner cell carrier (e.g., first bottom cell carrier) 202A can include a plurality of openings 204A. The second inner cell carrier (e.g., second bottom cell carrier) 202B can include a plurality of openings 204B. The first and second inner cell carriers 202A, 202B can include one or more of an electrically insulating material, a thermal insulating material, or a flame retardant material.

[0032] 3B shows a detailed view of the first inner cell carrier 202A. Each of the openings 204A of the first inner cell carrier 202A may include ribs 210A and windows 212A. The ribs 210A may be crushed together upon receiving a cell to provide an interference fit. Although only the first inner cell carrier 202A is shown, it should be appreciated that the second inner cell carrier 202B may include similar features.

[0033] FIG. 3C shows a detailed view of the retention feature. The first inner cell carrier 202A may include a first retention mechanism 206A disposed on the first inner cell carrier 204 and a second retention mechanism 208A disposed on the first inner cell carrier 202A. The first retention mechanism 206A may be configured to interlock with a second retention mechanism of the second inner cell carrier 202B. The retention mechanism may include at least one of a clip, a hook, a hook-and-loop fastener, a suction cup, an adhesive pad, an anchor, a dowel, a pin, a retaining ring, a snap fastener, a latch, or other fastener. Although only the first inner cell carrier 202A is shown, it is understood that the second inner cell carrier 202B may include similar features. The retention feature may serve to hold the two subassemblies 201A and 201B in a physically parallel configuration.

[0034] 4 illustrates two partially assembled subassemblies with cells disposed within the apertures. Each cell of the first set of cells 214A can be disposed within an aperture of the plurality of apertures 204A. Each cell can be held within the aperture through an interference fit between the aperture and the cell. The interference fit can result from squeezing one or more ribs 210A. Each cell of the first group of cells 214A can include a positive terminal and a negative terminal.

[0035] Each cell of the second set of cells 214B can be disposed within an opening of the plurality of openings 204B. Each cell can be held within the opening through an interference fit between the opening and the cell. This interference fit can be created by squeezing one or more ribs in the case of the second inner cell carrier 202B. Each cell of the second group of cells 214B can include a positive terminal and a negative terminal.

[0036] In embodiments of the present disclosure that include cylindrical cells, the entire exterior surface may include the negative terminal except for a small portion that is electrically insulated from the positive terminal.

[0037] FIG. 5A shows two subassemblies including first and second outer cell carriers 218A, 218B. The first subassembly 201A may include a first inner cell carrier (e.g., a first bottom cell carrier) 202A, a first group of cells 214A, and a first plurality of openings to receive the cells 204A. Additionally, the first subassembly 201A may include a first outer cell carrier 216A (e.g., a first top cell carrier) that may include a plurality of openings 224A adapted to receive the first set of cells 214A, a first lift point 218A, and a plurality of spacers 220A. The first lift point or contact point 218A may be utilized at a later stage of assembly to place the completed assembly in or out of the case 110. Additionally, the first lift point or contact point 218A may be vibration welded to the lid 120. Additionally, a number of spacers 220A can be utilized to position the first subassembly 201A within the case 110 and maintain a distance between the case 110 and the first outer cell carrier 216A. The first outer cell carrier 216A can include one or more of an electrically insulating material, a thermal insulating material, or a flame retardant material. The first subassembly 201A can include a first surface 226A configured to have a current collector 230 disposed thereon and a second surface 228A configured to interlock with the second subassembly 201B.

[0038] The second subassembly 201B may include a second inner cell carrier (e.g., a second bottom cell carrier) 202B, a second group of cells 214B, and a first plurality of openings for receiving the cells 204B. Additionally, the second subassembly 201B may include a second outer cell carrier 216B (e.g., a second top cell carrier), which may include a plurality of openings 224B adapted to receive the second set of cells 214B, a second lift point 218B, and a plurality of spacers 220B. The second lift point or contact point 218B may be utilized at a later stage of assembly to position the completed assembly in or out of the case 110. Additionally, the second lift point or contact point 218B may be vibration welded to the lid 120. Additionally, a number of spacers 220B may be utilized to position the first subassembly 201A within the case 110 and maintain a distance between the case 110 and the second outer cell carrier 216B. The second subassembly 201B may include a first surface 226B configured to have a current collector 230 disposed thereon and a second surface 228B configured to interlock with the first subassembly 201A.

[0039] 5B shows the first outer cell carrier 216A with a notch 222A around the opening 224A where the cell 214A is located. This feature allows for increased flexibility in assembling batteries with various voltages, currents and energies from a common component. The notch in the top cell carrier provides flexibility in the placement of the flexible current collector 230 to facilitate different architectures based on a common component while only changing the pattern of the conductors on the flexible current collector. Although only the first outer cell carrier 216A is shown, it should be understood that the second outer cell carrier 216B can have similar features with similar functionality.

[0040] FIG 6 shows a partially assembled assembly with the flexible current collector attached. Flexible current collector 230 may be a single plate containing multiple conductive regions. Referring to FIGs 9A and 9B, multiple conductive regions 229a-g are shown. Returning to FIG 6, each conductive region may additionally or alternatively include an integrated fuse 234A and 234B, thereby eliminating the need for a fuse in the wire harness 232 found in conventional batteries.

[0041] For example, the flexible current collector 230 may include a layered flexible current collector 230. The layers within the flexible current collector 230 may provide voltage sensing, fusible elements, reference points, and may conduct electricity. For example, one layer may be a copper conductive layer and the other layer may be a non-conductive layer. This allows each cell to be connected to the conductive layers in series and / or parallel groups.

[0042] In an example, the flexible current collector 230 may be bendable (e.g., foldable) without breaking or lasting damage. The flexible current collector 230 may reduce the number of joints in the module, leading to lower resistance and easier manufacturing. The flexible current collector 230 may be bendable about a center point, line, or other axis comparable to a hinge. The flexible current collector 230 may include one or more bends such that the flexible current collector 300 has a substantially "U" shaped profile in the bent configuration.

[0043] In an example, the flexible current collector 230 may comprise a stamped or printed fusible link. The flexible current collector 230 may include a variety of suitable materials and coatings. The flexible current collector 230 may be mechanically and electrically connected to the battery cells to form subgroups of battery cells connected in series and / or parallel. The subgroups of cells may be connected in series and / or parallel with other subgroups of cells by the flexible current collector 230.

[0044] 7 shows details of a partially assembled assembly with fusible links. In an example, the flexible current collector 230 can be connected to the cell by wire bonding, laser welding, adhesive or other suitable conductive connection.

[0045] The fusible link 236A can conduct current from the cells to the current collectors. The fusible link 236A can act as a fuse that breaks the connection between the individual cells and the current collectors at the appropriate current level. This can increase safety by preventing combustion or thermal events. Specifically, the fusible link can melt to disconnect the cell from the current collector and therefore from the remaining cells. This design can be tailored for the desired voltage and / or current. The exact parameters of the fusible link 236A can be controlled by varying the shape, thickness, width and / or material composition of the fusible link 236A.

[0046] The fusible link 236A may be integrally formed within the current collector. The structure of the fusible link 236A may be modified to meet various functional, performance or safety requirements depending on the particular product design and use.

[0047] The fusible link 236A may include a wire bond, laser welded connection, or ribbon bond to join the current collector to the cell as a fuse. Multiple alternative shapes and designs of the fusible link can perform the same function. Those skilled in the art will appreciate that the shape of the fusible link may depend on individual specifications such as cell-to-cell variations, fusing characteristics, materials, cell type, manufacturing process, and intended application. In certain embodiments, the fusible link may be a laser welded stamped fusible link.

[0048] The fusible link can enhance the safety of the entire battery. The fusible link can provide a fuse function to the current collector without requiring special processes or additional components that can introduce substantial variations and potential errors. The fusible link can be connected to the battery cell terminals using either resistance welding, laser welding, wire bonding, adhesives, or other conductive connections.

[0049] 8A and 8B show a flexible current collector 230 that may include one or more layers 231a, 231b, and / or 231c. In an example, the flexible current collector 230 may include a first layer 231a, which may include a pressure sensitive adhesive configured to bond to the first surfaces 226A, 226B of the first and second subassemblies 201A, 201B. The second layer 231b may include a conductor, for example, copper or aluminum. The second layer 231b may include aluminum, copper, or other conductive metal, and may be configured to receive one or more wire bonds or other suitable connections from one or more of the first group of cells 214A or the second group of cells 214B. The third layer 231c may include a plastic layer, for example, PET.

[0050] In an embodiment, the flexible current collector is designed to conduct 400A (preferably 450A) for 30 seconds and 120A (preferably 150A) continuous current. The thickness of the copper to conduct these current loads is preferably 0.20-0.25mm. Holes can be added at the bend corners to aid in bending and buckling of the current collector. Wire bonds are preferably not placed near the folds. Figures 13 and 14 show two alternative current collectors. The negative notches in the conductors are preferably positioned to align with the separation between the conductors to retain the conductor material.

[0051] In an alternative embodiment, as shown in Figure 8B, the flexible current collector 230 need not include the first layer 231a and can be attached to the subassemblies 201A, 201B using mechanical fasteners. Additionally, the flexible current collector 230 provides substantial flexibility and can be adapted to conduct current in a number of alternative configurations. Sufficient current collector cross-section is preferably maintained so as not to add heat or impair current transport.

[0052] In alternative embodiments of the present disclosure adapted for high voltage applications, a fourth layer may be added to include a further conductive layer and deposited on the third layer 231c. The fourth layer may include aluminum, copper or other conductive metal and may be configured to receive one or more wire bonds or other suitable connections from one or more of the first group of cells 214A or the second group of cells 214B. The fourth layer may include multiple conductive regions, e.g., multiple conductive regions.

[0053] 9A and 9B show a current collector 230 having multiple conductive regions 229A-229G and the folded assembly from a first angle and a second angle. Cells numbered 1-7 are shown for illustrative purposes to represent subgroups of cells. Each conductive region 229A-229G can be electrically connected to various battery components via connections 232.

[0054] In certain embodiments, the conductive region 229D may "wrap around" to the opposite side of the assembly 200. The flexible current collector 230 may be configured to allow the battery cells to be connected in series and / or parallel.

[0055] FIG. 10A is a schematic perspective view of a partially exploded embodiment of the present disclosure showing an air gap disposed between the two subassemblies and the flexible current collector of an embodiment of the present disclosure. In certain embodiments of the present disclosure, a cold plate or heat sink material can be disposed between the first inner cell carrier 202A and the second inner cell carrier 202B to transfer heat away from the module. The cold plate is electrically insulated from the negative terminal of the cell. An embodiment of the present disclosure may include a heat transfer material disposed in this air gap between the bottom of the cell and the cold plate to facilitate heat transfer while maintaining electrical insulation.

[0056] In certain embodiments, a heat sink or cold plate can be disposed between the subassemblies in the folded orientation. The cold plate or heat sink can be actively cooled, e.g., a water-cooled or fan-cooled heat sink. Additionally or alternatively, the cold plate or heat sink can be passively cooled, whereby the cold plate or heat sink can be configured to dissipate heat substantially by natural convection. Alternatively, the battery 100 can utilize an air gap between the first subassembly 201A and the second subassembly 201B, and need not include a cold plate or heat sink disposed between the two subassemblies connected by the folded flexible current collector 230.

[0057] 10B is a detailed perspective schematic view of the retaining feature. As described above, the second retaining feature 208A of the first inner cell carrier 202A may interlock with the first retaining feature 206B of the second inner cell carrier 202B. This retaining feature may serve to hold the two subassemblies 201A and 201B in a physically parallel configuration.

[0058] 11A-11E are diagrams of the assembly of a battery according to a preferred embodiment of the present disclosure.

[0059] 11B illustrates attachment of the BMS 300 to the assembly 200. The BMS 300 may include a heat sink 302, a first integrated terminal 304, and a second integrated terminal 306. The BMS 300 may be electrically connected to the assembly 200. The BMS may include one or more processors, a memory having instructions that, when executed, cause the BMS 300 to perform one or more functions. The one or more functions may include managing electrical and / or thermal loads, detecting errors, or sending or receiving data from an external computing device.

[0060] 11C shows the harness 232 of the current collector 230 connecting to the BMS receptacle 308. Additionally, the lid 120 can be placed over the BMS 300 and physically connected to the case 110. Additionally, the BMS 300 can be electrically connected to the wire harness in the lid 120.

[0061] FIG. 11D shows the installation of the vent 122 within the vent hole 124. Prior to installation of the vent 122, several quality and / or safety checks can be performed. For example, electrical checks can be performed to verify the integrity of the various electrical connections. The lid 120 can be vibration welded to the case 110. A leak check can be performed to verify the physical integrity of the battery 100. A foam, liquid, or gel can be injected into the case 110 through the vent hole 124 and placed around the cells to fill the spaces between the cells and between the cells and the inner surface of the casing. The foam, liquid, or gel can provide thermal insulation and prevent the propagation of thermal events between the individual cells. The foam, liquid, or gel can also provide structural support by resisting vibration and aiding in the mechanical retention of the battery cells and components. The foam, liquid, or gel can provide thermal insulation, deflect and direct exhaust gases, and absorb radiant heat.

[0062] FIG. 11E shows the battery 100.

[0063] Figure 12 illustrates a method for manufacturing battery 100. The basic steps of an exemplary method are illustrated in Figure 12. Of course, the steps comprising the method can be altered, combined, omitted, reordered, or otherwise modified according to the target specifications for the battery.

[0064] At block 402, the method 400 may include inserting the cells into the cell carrier. The inner and outer cell carriers are preferably adapted to receive the cells by an interference fit, with or without an insert to facilitate insertion of the cells into the cell carrier. In an embodiment, an insert may be placed in a recess in the inner cell carrier to electrically isolate each cell from the cold plate while placing the cells in sufficient proximity to the cold plate to promote effective heat transfer. Alternatively, in a preferred embodiment, the parts may be provided by the manufacturer with threaded inserts installed.

[0065] At block 404, the method 400 may include mounting a thermistor proximate to one or more cells.

[0066] At block 406, the method 400 may include connecting the positioned cells to the flexible current collector. Additionally or alternatively, the cells may be a first group of cells and the method 400 may further include connecting a second group of positioned cells to the flexible current collector. Additionally or alternatively, the cells may be a first group of cells and the outer cell carrier may be a first outer cell carrier and the method 400 may further include coupling the flexible current collector to the second outer cell carrier. Additionally or alternatively, coupling the flexible current collector to the second outer cell carrier may further include folding the flexible current collector such that the first and second inner cell carriers are physically oriented substantially parallel to one another, engaging retention features to retain the configuration of the first and second inner cell carriers, and wire bonding a first terminal to a first conductive region of the flexible current collector. Additionally or alternatively, coupling the flexible current collector to the second outer cell carrier may further include wire bonding a first terminal to a first conductive region of the flexible current collector, folding the flexible current collector so that the first and second inner cell carriers are adjacent to one another, and engaging retention features to retain the configuration of the first and second inner cell carriers.

[0067] At block 408, the method 400 may include press forming the subassembly. The method 400 may include placing the cells in an inner cell carrier (e.g., a bottom cell carrier). The cells may be lithium ion cells. Additionally or alternatively, the cells may include a first group of cells, the inner cell carrier may include a first inner cell carrier, and the method may further include placing a second group of cells in the second inner cell carrier. In an example, the cells may include a first terminal and a second terminal. The terminals may be terminals of the cells, e.g., the first terminal may be a positive terminal of the cell and the second terminal may be a negative terminal of the cell. The placement of each cell in the first and / or second inner cell carrier may be performed using a robot or other automated mechanism. In an example, the orientation of the cells (e.g., the orientation of the first and / or second terminals) may be oriented away from the other cells. In another example, the orientation of the cells may be such that the tabs are proximate to the housing. Method 400 may include disposing an outer cell carrier (e.g., a top cell carrier) over the positioned cells, the outer cell carrier including a plurality of recesses configured to receive each of the cells. Additionally or alternatively, the cells may be a first group of cells and the outer cell carrier may be a first outer cell carrier, and method 400 may further include disposing a second outer cell carrier over the positioned second group of cells, the second outer cell carrier including a plurality of recesses configured to receive each of the second group of cells.

[0068] At block 408, the method 400 may include electrically connecting the cells to current collectors.

[0069] At block 412, the method 400 may include folding the current collector and subassembly (and heat sink, if utilized).

[0070] At block 416, the method 400 may include installing a battery management system and electrically connecting the battery management system to the current collectors.

[0071] At block 418, the method 400 may include vibration welding the lid and case together. In an example, the lid may be connected to the housing using vibration welding. The vibration welding may fuse the lid material and the housing material to unite the lid material and the housing. Additionally, the lid may be vibration welded to the subassembly at the lift points (e.g., first and second lift points 211, 221). The vibration welding process may fuse the lift points to the lid to unite the assembly with the lid.

[0072] At block 420, the method 400 may include potting the one or more terminals with an epoxy resin.

[0073] At block 422, the method 400 may include injecting a foam into the housing. In an example, the foam, liquid, or gel may be placed around the cells within the casing to fill the spaces between the cells and between the cells and the inner surface of the casing. The foam, liquid, or gel may provide thermal insulation and may prevent the propagation of thermal events between individual cells. The foam, liquid, or gel may also provide structural support by resisting vibration and aiding in mechanical retention of the battery cells and components. The foam, liquid, or gel may provide thermal insulation, deflect and direct exhaust gases, and absorb radiant heat.

[0074] At block 424, the method 400 may include attaching a vent (e.g., vent 105) to the lid. The vent may include a pressure sensitive permeable membrane that may be configured to rupture above a predetermined pressure threshold. For example, the pressure sensitive membrane may be configured to rupture at 25 psi (e.g., 25 psi above the ambient air pressure). When the internal air pressure within the battery reaches or exceeds 25 psi above the ambient air pressure, the pressure sensitive membrane ruptures, allowing the internal pressure of the battery to be released and reach equilibrium with the environment or ambient air pressure. The permeable membrane may also allow pressure equalization between the battery and the environment, for example, during transportation by aircraft.

[0075] FIG. 13 shows an example of a current collector for a 24V battery, according to an embodiment of the present disclosure.

[0076] FIG. 14 illustrates an example of a current collector for a 48V battery, according to an embodiment of the present disclosure.

[0077] FIG. 15 shows an exploded view of two subassemblies, a flexible current collector, and a heat sink according to an embodiment of the present disclosure.

[0078] FIG. 16A shows a 48V battery using a cell carrier according to a preferred embodiment of the present disclosure.

[0079] FIG. 16B illustrates an alternative 48V battery using the cell carrier of FIG. 16A in accordance with a preferred embodiment of the present disclosure, whereby some of the spaces for cells within the carrier are left empty to provide lower capacity or energy without modifying other components of the battery or the battery's manufacturing process.

[0080] Example 1: A group of 24 cells was electrically connected in parallel, and each of the 3.5 groups of 24 cells was electrically connected in series to form a subassembly. Two such subassemblies were prepared and electrically connected by a flexible current collector. A wrap-around portion of the current collector connected the two 3.5 groups in parallel. The two subassemblies were folded toward each other with the current collector on the outside and, if a heat sink was used, the heat sink was placed between the inside faces of the two subassemblies. If an electrically conductive heat sink was used, an electrically insulating, thermally conductive interface material was placed on the exposed surfaces of the cells on the two open faces of the subassembly. The two subassemblies were then brought together, closed, and locked, with the heat sink placed in place between the two subassemblies.

[0081] This assembly was then placed into the lower portion of the case, and the BMS was then installed and electrically connected to the electrical contacts on the assembly and lid. Electrical checks were performed to determine validity and operability of the electrical components. The lid was vibration welded to the lower case. The terminals were sealed to the lid. A leak check was performed to verify the integrity of the housing assembly. Foam was then injected through the open vent hole in the lid while the case was held at a 10.5 degree angle to facilitate venting of off-gassing during curing and to completely fill the space between the cells. For the GC2 battery in this example, the fill was 987g, completely covering the cells. The vent was then installed in the lid.

[0082] The resulting GC2 battery has a nominal voltage of 25.8 V and a nominal capacity of 118 Ah.

[0083] Example 2: Ten cells were electrically connected in parallel to form groups, and sixteen groups of ten cells were each electrically connected in series to form a subassembly. Two such subassemblies were prepared and electrically connected in series by flexible current collectors. The two subassemblies were folded toward each other with the current collectors on the outside and, if a heat sink was used, a heat sink between the inside faces of the two subassemblies. If an electrically conductive heat sink was used, an electrically insulating, thermally conductive interface material was placed on the exposed surfaces of the cells on the two open faces of the subassembly. The two subassemblies were then brought together, closed, and locked, with the heat sink in place between the two subassemblies.

[0084] This assembly was then placed into the lower portion of the case, and the BMS was then installed and electrically connected to the electrical contacts on the assembly and lid. Electrical checks were performed to determine validity and operability of the electrical components. The lid was vibration welded to the lower case. The terminals were sealed to the lid. A leak check was performed to verify the integrity of the housing assembly. Foam was then injected through the open vent hole in the lid while the case was held at a 10.5 degree angle to facilitate venting of off-gassing during curing and to completely fill the space between the cells. For the GC2 battery in this example, the fill was 987g, completely covering the cells. The vent was then installed in the lid.

[0085] The resulting GC2 battery has a nominal voltage of 36.9 V and a nominal capacity of 79 Ah.

[0086] Example 3 Twelve cells were electrically connected in parallel to form groups, and seven groups of twelve cells were each electrically connected in series to form a subassembly. Two such subassemblies were prepared and electrically connected in series by flexible current collectors. The two subassemblies were folded toward each other with the current collectors on the outside and, if a heat sink was used, a heat sink between the inside faces of the two subassemblies. If an electrically conductive heat sink was used, an electrically insulating, thermally conductive interface material was placed on the exposed surfaces of the cells on the two open faces of the subassembly. The two subassemblies were then brought together, closed, and locked, with the heat sink in place between the two subassemblies.

[0087] This assembly was then placed into the lower portion of the case, and then the BMS was installed and electrically connected to the electrical contacts on the lid assembly. Electrical checks were performed to determine validity and operability of the electrical components. The lid was vibration welded to the lower case. The terminals were sealed to the lid. A leak check was performed to verify the integrity of the housing assembly. Foam was then injected through the open vent hole in the lid while the case was held at a 10.5 degree angle to facilitate venting of off-gassing during curing and to completely fill the space between the cells. For the GC2 battery in this example, the fill was 987g, completely covering the cells. The vent was then installed in the lid.

[0088] The resulting GC2 battery has a nominal voltage of 51.7 V and a nominal capacity of 59 Ah.

[0089] Example 4: Fourteen cells were electrically connected in parallel to form groups, and eight groups of fourteen cells were each electrically connected in series to form a subassembly. Two such subassemblies were prepared and electrically connected in series by flexible current collectors. The two subassemblies were folded toward each other with the current collectors on the outside and, if a heat sink was used, a heat sink between the inside faces of the two subassemblies. If an electrically conductive heat sink was used, an electrically insulating, thermally conductive interface material was placed on the exposed surfaces of the cells on the two open faces of the subassembly. The two subassemblies were then brought together, closed, and locked, with the heat sink in place between the two subassemblies.

[0090] This assembly was then placed into the lower portion of the case, and the BMS was then installed and electrically connected to the electrical contacts on the assembly and lid. Electrical checks were performed to determine validity and operability of the electrical components. The lid was vibration welded to the lower case. The terminals were sealed to the lid. A leak check was performed to verify the integrity of the housing assembly. Foam was then injected through the open vent hole in the lid while the case was held at a 10.5 degree angle to facilitate venting of off-gassing during curing and to completely fill the space between the cells. For the GC2 battery in this example, the fill was 987g, completely covering the cells. The vent was then installed in the lid.

[0091] Of course, the battery cells can be inspected prior to inclusion in a battery module. Inspection can include human or automated verification that each cell is free of visible defects or structural damage, that each cell is within physical measurement specifications, that each cell meets material composition and chemical specifications, and that each cell is generally suitable for incorporation into a battery module. Battery cells can also be prepared for inclusion in a battery subassembly by removing or disassembling any temporary or excess housing or packaging.

[0092] The description of various embodiments of the present disclosure is presented for illustrative purposes and is not intended to be comprehensive or limiting. Multiple modifications and variations of the disclosed embodiments will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terms used in this specification are selected in order to most clearly explain the principles of the embodiments, practical applications or technical improvements to the technology found in the market, or to allow other skilled in the art to understand the embodiments disclosed herein.

[0093] Certain features of the present disclosure that are, for clarity, described in the context of separate embodiments, may also be combined in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination, or as appropriate, with any other described embodiment of the disclosure. Certain features described in the context of various embodiments should not be construed as essential features of those embodiments, unless the embodiment is inoperable without those elements.

[0094] While the disclosure has been described in conjunction with specific embodiments thereof, many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the spirit and broad scope of the appended claims.

Claims

1. A battery, Cells electrically connected to form a group; a group of cells electrically connected to form a first subassembly and a second subassembly; a first subassembly including a lower tray and an upper tray with a first group of cells disposed therebetween, the first subassembly having first and second faces; a second subassembly including a lower tray and an upper tray with a second group of cells disposed therebetween, the second subassembly having first and second faces; a flexible current collector including two or more conductive regions; Equipped with the first and second subassemblies being electrically connected to establish a voltage or capacity of the battery; the flexible current collector electrically connects the first and second subassemblies and is disposed within a casing to provide environmental protection for the battery; positive and negative terminals electrically connected to the first and second conductive regions to form, respectively, the positive and negative terminals of the battery; a battery management system electrically connected to the flexible current collector and to positive and negative terminals adapted to control the flow of energy through the battery; The battery.

2. 10. The battery of claim 1, wherein the flexible current collector is electrically connected to the first sides of the first and second subassemblies.

3. 3. The battery of claim 2, wherein the current collector and the first and second subassemblies are folded such that the second faces of the first and second subassemblies are disposed adjacent to one another, the battery further comprising a heat sink disposed between the second faces of the first and second subassemblies.

4. a first battery; The first battery includes using the same components to generate a second battery; capacity is added by increasing the number of cells in at least one of said first or second subassemblies; or 10. The battery of claim 1, wherein capacity is reduced by reducing the number of cells in at least one of the first or second subassemblies.

5. a first battery including a first current collector; further comprising creating a second battery using the same components and a second current collector; 10. The battery of claim 1, wherein the second current collector includes a different conductive region that is electrically connected, and the second battery has a different voltage than the first battery or a different capacity than the first battery.

6. a first battery including a first current collector; further comprising creating a second battery using the same components and a second current collector; 10. The battery of claim 1, wherein the second current collector includes a different conductive region that is electrically connected, and the second battery has a different voltage and the same energy as the first battery, or a different capacity and the same energy as the first battery.

7. a first battery including a first current collector; generating a second battery having a different voltage using the same components and a second current collector, the second current collector including different electrically connected conductive regions; capacity is added by increasing the number of cells in at least one of said first or second subassemblies; or 10. The battery of claim 1, wherein capacity is reduced by reducing the number of cells in at least one of the first or second subassemblies.

8. The flexible current collector further comprises one or more layers, the layers comprising: a conductive layer including a pattern defining a plurality of conductive regions; A separation layer; The battery of any one of claims 1 to 7, comprising:

9. The flexible current collector further comprises one or more layers, the layers comprising: A pressure sensitive adhesive layer; a conductive layer including a pattern defining a plurality of conductive regions; A separation layer; The battery of any one of claims 1 to 7, comprising:

10. The battery of any one of claims 1 to 7, wherein the flexible current collector is electrically connected to the first sides of the first and second subassemblies by wire bonding or by laser welding.

11. 4. The battery of claim 3, wherein the flexible current collector includes one or more bends such that the flexible current collector has a substantially "U" shaped profile.

12. The battery, a case configured to house one or more subassemblies; a lid configured to form a seal between the lid and the case; and The battery of any one of claims 1 to 7, further comprising:

13. 1. A method of assembling a battery, comprising: inserting cells into inner and outer trays of first and second carriers to form two subassemblies; disposing a current collector; electrically connecting the cell to a current collector; folding the current collector and the subassembly; and The method comprising:

14. Electrically connecting the cell to the current collector includes wire bonding a first terminal to a first conductive region of the flexible current collector; and / or Folding the current collector and the subassembly folding the flexible current collector so that the first bottom cell carrier and the second bottom cell carrier are substantially parallel to one another; engaging a retention feature to retain the configuration of the first bottom cell carrier and the second bottom cell carrier; The method of claim 13, comprising:

15. placing the subassembly within a case; electrically connecting a battery management system to the subassembly; vibration welding the lid to the case; attaching a thermistor to one or more of said cells; epoxying one or more terminals; injecting a foam into the casing; Attaching a vent to the lid; 15. The method of claim 13 or 14, further comprising:

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